Web sites provide a variety of content for users to view, hear, download, and otherwise interact with. Web sites also receive user attribute data, such as user profile data, user interaction data, user likes/dislikes, user wants, etc. Some user attribute data is collected passively as a user interacts with a web site; other user attribute data is supplied directly to a web site by a user. The collection and organization of this user attribute data into a useful set of information is a complicated task.